Known systems are configured to register user information in an information center, which is communicable with a portable terminal device such as a mobile phone, and to perform user authentication on the basis of the registration information when providing a variety of services. For example, in a system disclosed in JP-A-2004-248042, a user ID is issued to a user who has completed user registration processing. In addition, when the user ID is input to a vehicular device, the user ID is transmitted from the vehicular device to the information center, and the information center performs user authentication.
In the above system, the user needs to input the user ID to the vehicular device when the user receives a variety of services. This input operation may take time and may require burden to the user. In addition, one vehicular device and one mobile phone are generally associated with each other and are generally registered for each user in the above system. Accordingly, when a person other than the registered user wants to receive a variety of services, for example, when family or friends of the registered user want to use the variety of services, a complicated procedure, such as rewriting the registration information, is required. In addition, when the user wants to use a variety of services in a rental car, for example, the user should also input the user ID to a vehicular device of the rental car. Accordingly, the user ID which is a kind of personal information may be leaked to others. Thus, since the system of the related art may not be user-friendly, further improvements have been desired.